N-Heterocyclic carbene (NHC)–copper-catalysed transformations of carbon dioxide

This minireview gives an overview of the chemical transformations of carbon dioxide (CO2) catalysed by N-heterocyclic carbene (NHC)–copper complexes. NHC–copper complexes can serve as excellent catalysts for the carboxylation of various substrates with CO2 and the reduction of CO2 to CO or formic acid derivatives. In addition, NHC ligands enable the isolation of structurally characterisable key reaction intermediates, thus helping in understanding the mechanistic details of the catalytic processes. The related reactions catalysed by other metal complexes with NHC ligands are also briefly described.